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We examine the impact of new supervisory standards for bank trading portfolios, additional capital requirements for liquidity risk and credit risk (the Incremental Risk Charge), introduced under Basel 2.5. We estimate risk measures under alternative assumptions on portfolio dynamics (constant level of risk vs. constant positions), rating systems (through-the-cycle vs. point-in-time), for different sectors (asset classes and industry groups), alternative credit risk frameworks (al-ternative dependency structures or factor models) and an extension to a Bayesian framework. We find a potentially material increase in capital requirements, above and beyond that concluded in the far-ranging impact studies conducted by the international supervisors utilizing the participation of a large sample of banks. Results indicate that capital charges are in general higher for either point-in-time ratings or constant portfolio dynamics, with this effect accentuated for financial or sovereign as compared to industrial sectors; and that regulatory is larger than economic capital for the latter, but not for the former sectors. A comparison of the single to a multi-factor credit models shows that capital estimates larger in the latter, and for the financial / sovereign by orders of magnitude vs. industrial or the Basel II model, and that there is less sensitivity of results across sectors and rating systems as compared with the single factor model. Furthermore, in a Bayesian experiment we find that the new requirements may introduce added uncertainty into risk measures as compared to existing approaches.